Donate to e Foundation | Murena handsets with /e/OS | Own a part of Murena! Learn more

Commit bec444cd authored by Johan Hovold's avatar Johan Hovold Committed by Greg Kroah-Hartman
Browse files

USB: hub: fix non-SS hub-descriptor handling 



Add missing sanity check on the non-SuperSpeed hub-descriptor length in
order to avoid parsing and leaking two bytes of uninitialised slab data
through sysfs removable-attributes (or a compound-device debug
statement).

Note that we only make sure that the DeviceRemovable field is always
present (and specifically ignore the unused PortPwrCtrlMask field) in
order to continue support any hubs with non-compliant descriptors. As a
further safeguard, the descriptor buffer is also cleared.

Fixes: 1da177e4 ("Linux-2.6.12-rc2")
Cc: stable <stable@vger.kernel.org>     # 2.6.12
Signed-off-by: default avatarJohan Hovold <johan@kernel.org>
Acked-by: default avatarAlan Stern <stern@rowland.harvard.edu>
Signed-off-by: default avatarGreg Kroah-Hartman <gregkh@linuxfoundation.org>
parent 2c25a2c8

drivers/usb/core/hub.c

+9 −4
Original line number Diff line number Diff line
@@ -362,7 +362,8 @@ static void usb_set_lpm_parameters(struct usb_device *udev) 
}



/* USB 2.0 spec Section 11.24.4.5 */

static int get_hub_descriptor(struct usb_device *hdev, void *data)

static int get_hub_descriptor(struct usb_device *hdev,

		struct usb_hub_descriptor *desc)

{

	int i, ret, size;

	unsigned dtype;
@@ -378,12 +379,16 @@ static int get_hub_descriptor(struct usb_device *hdev, void *data) 
	for (i = 0; i < 3; i++) {

		ret = usb_control_msg(hdev, usb_rcvctrlpipe(hdev, 0),

			USB_REQ_GET_DESCRIPTOR, USB_DIR_IN | USB_RT_HUB,

			dtype << 8, 0, data, size,

			dtype << 8, 0, desc, size,

			USB_CTRL_GET_TIMEOUT);

		if (hub_is_superspeed(hdev)) {

			if (ret == size)

				return ret;

		} else if (ret >= (USB_DT_HUB_NONVAR_SIZE + 2)) {

		} else if (ret >= USB_DT_HUB_NONVAR_SIZE + 2) {

			/* Make sure we have the DeviceRemovable field. */

			size = USB_DT_HUB_NONVAR_SIZE + desc->bNbrPorts / 8 + 1;

			if (ret < size)

				return -EMSGSIZE;

			return ret;

		}

	}
@@ -1317,7 +1322,7 @@ static int hub_configure(struct usb_hub *hub, 
	}

	mutex_init(&hub->status_mutex);



	hub->descriptor = kmalloc(sizeof(*hub->descriptor), GFP_KERNEL);

	hub->descriptor = kzalloc(sizeof(*hub->descriptor), GFP_KERNEL);

	if (!hub->descriptor) {

		ret = -ENOMEM;

		goto fail;